Repulsive store for headless chicken (7)
I believe the answer is:
rooster
'chicken' is the definition.
(I know that rooster is a type of chicken)
'repulsive store for headless' is the wordplay.
I cannot really see how this works, but
an anagram of 'store' is 'oster' which is located in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for rooster that I've seen before include "Early-morning caller" , "Morning caller" , "Male hen" , "Adult male domestic fowl" , "Male domestic fowl in USA" .)